In short, I am looking for someone experienced in Arizona tax law, especially with regard to foreign software businesses doing business in Arizona. I am a sole proprietor registered in Europe and run a software company. I have a business client in Arizona who will use our cloud-hosted software that only they will use to generate text translations. They will be invoiced for their usage (so NOT a subscription, I think this is important due to how Arizona defined SaaS/cloud computing which is a taxable service). The invoice amount will exceed 100k USD/year. I am looking for someone who can tell me whether I need to pay sales tax in Arizona.